1. Field of Invention
This invention relates to drive-up ordering stations in fast food restraints. Specifically to. the sound system of remote ordering by sound speaker & microphone connection.
2. Prior Art
Doi (U.S. Pat. No. 4,037,052) has a paraboloid pickup (microphone) assembly. Srour etal, (U.S. Pat. No. 4,964,100) has a similar acoustical detector with paraboloid reflector. Zlevor (U.S. Pat. No. 4,264,790) shows a portable directional microphone that has a paraboloid reflector. All of these systems do not have a bidirectional communication of the paraboloid reflector.
Saylors (U.S. Pat. No. 4,313,183) teaches a way to determine distance by sonar methods. However, it does not require triangulation technique.